MCP 2025 Patterns

MCP 2025 Patterns

This skill covers current best practices for Model Context Protocol (MCP) server design, implementation, and integration as of late 2025.

MCP Architecture Fundamentals

Core Concepts

┌─────────────────────────────────────────────────────────────┐
│                    Claude Code (Host)                        │
├─────────────────────────────────────────────────────────────┤
│  MCP Client Layer                                           │
│  ├── Server Discovery & Connection                          │
│  ├── Tool Registration & Invocation                         │
│  ├── Resource Management                                    │
│  └── Prompt Templates                                       │
├─────────────────────────────────────────────────────────────┤
│  MCP Servers (Multiple)                                     │
│  ├── github-mcp (repositories, issues, PRs)                 │
│  ├── notion-mcp (pages, databases, blocks)                  │
│  ├── linear-mcp (issues, projects, cycles)                  │
│  ├── custom-mcp (your domain-specific tools)                │
│  └── ...                                                    │
└─────────────────────────────────────────────────────────────┘

MCP Server Components

1. Tools: Functions the AI can invoke
2. Resources: Data the AI can read
3. Prompts: Template prompts for common tasks
4. Notifications: Server-to-client events

Server Design Patterns

Pattern 1: Single Responsibility Server

// Good: Focused server for one domain
const server = new MCPServer({
  name: "github-mcp",
  version: "1.0.0"
});

// Tools all relate to GitHub
server.addTool("create_issue", createIssueHandler);
server.addTool("list_pulls", listPullsHandler);
server.addTool("merge_pr", mergePRHandler);

Pattern 2: Resource-First Design

// Define resources before tools
server.addResource({
  uri: "github://repos/{owner}/{repo}",
  name: "Repository",
  description: "GitHub repository data and metadata",
  mimeType: "application/json"
});

// Tools operate on resources
server.addTool({
  name: "get_repo",
  description: "Fetch repository details",
  inputSchema: {
    type: "object",
    properties: {
      owner: { type: "string" },
      repo: { type: "string" }
    },
    required: ["owner", "repo"]
  }
});

Pattern 3: Hierarchical Tool Organization

// Organize tools by domain/action
const tools = {
  // Issues domain
  "issues_create": createIssue,
  "issues_update": updateIssue,
  "issues_list": listIssues,
  "issues_close": closeIssue,

  // PRs domain
  "pulls_create": createPR,
  "pulls_merge": mergePR,
  "pulls_review": reviewPR,

  // Repos domain
  "repos_list": listRepos,
  "repos_create": createRepo
};

Tool Design Best Practices

Clear, Action-Oriented Names

// Good: Clear action + noun
"create_issue"
"list_repositories"
"merge_pull_request"
"search_code"

// Bad: Vague or ambiguous
"do_github"
"handle_request"
"process_data"

Comprehensive Input Schemas

server.addTool({
  name: "create_issue",
  description: "Create a new GitHub issue with title, body, labels, and assignees",
  inputSchema: {
    type: "object",
    properties: {
      owner: {
        type: "string",
        description: "Repository owner (user or org)"
      },
      repo: {
        type: "string",
        description: "Repository name"
      },
      title: {
        type: "string",
        description: "Issue title",
        minLength: 1,
        maxLength: 256
      },
      body: {
        type: "string",
        description: "Issue body (Markdown supported)"
      },
      labels: {
        type: "array",
        items: { type: "string" },
        description: "Labels to apply"
      },
      assignees: {
        type: "array",
        items: { type: "string" },
        description: "GitHub usernames to assign"
      }
    },
    required: ["owner", "repo", "title"]
  }
});

Structured Output Formats

// Return structured, predictable data
async function createIssue(params) {
  const issue = await github.issues.create({...});

  return {
    success: true,
    issue: {
      number: issue.number,
      url: issue.html_url,
      title: issue.title,
      state: issue.state,
      created_at: issue.created_at
    },
    // Include actionable next steps
    suggested_actions: [
      `Add labels: /api/issues/${issue.number}/labels`,
      `Assign team: /api/issues/${issue.number}/assignees`
    ]
  };
}

Reference

The full detail lives in references/ and loads only when needed:

• references/advanced-patterns.md — security, multi-server orchestration, performance, error handling & testing patterns.

FrankX System Integration

Current MCP Servers in Use

• github-mcp: Repository management, issues, PRs
• linear-mcp: Project management, issues, cycles
• notion-mcp: Documentation, databases, pages
• nano-banana-mcp: Image generation
• n8n-mcp: Workflow automation
• playwright-mcp: Browser automation

Best Practices for FrankX

1. Server per domain: Keep MCPs focused (GitHub for code, Linear for tasks)
2. Consistent naming: mcp__<server>__<action> format
3. Graceful fallbacks: If MCP unavailable, suggest alternative
4. Context awareness: Use right MCP for right task automatically

MCP servers extend Claude's capabilities with real-world integrations. Design them with clear responsibility, robust error handling, and security in mind.